iOS 5 also featured deep integration with Twitter, introduced multitasking gestures on iPads, and added an easily accessible camera shortcut from the lock screen.

iOS 5 was the subject of criticism for iPhone 4s users, as the initial release had poor battery life, failures of SIM cards, and echoes during phone calls.

[4][5] In previous iOS versions, notifications popped up on the screen as dialog boxes, interrupting the current activity.

The new service allows users to synchronize their music, photos, videos, and application data across all of their iCloud-enabled devices for free.

The first iOS 5 release allowed the Camera app to be easily accessed from the lock screen for the first time.

[7] The Mail app included rich text formatting, better indent control, flagging of messages, and the ability to drag addresses between To, CC, and BCC lines.

[13][25] The initial October 2011 release of iOS 5 saw significant upgrade issues, with errors during installation and Apple server overload.

[31] In November 2011, Engadget reported that the iOS 5 update caused Wi-Fi connection drops for some users.

The report also wrote that "The recent iOS 5.0.1 update certainly hasn't fixed the matter, either", and questioned whether the events were unrelated or part of a larger issue.

[33] Apple released a second software build of the 5.0.1 update designed to fix SIM card issues.

[34] Some iPhone 4s users reported the random appearance of echoes during phone calls made with earphones in the initial release of iOS 5.

[35][36] Many aspects of iOS 5 received positive reviews, including the new notification center, the ability to sync and update wirelessly, iMessage, and more.